Question { Google, 29360 }

why oscillators are used in micro controllers?

Answer

The main purpose of the oscillator in PICmicro
microcontrollers,
or almost any other microcontroller, is to
provide a reliable clock for the controller processes. At
the most basic level, the clock provides a timing interval
to account for circuit rise times and to allow data to
stabilize before that data is processed. This is a
"synchronous" process. The clock also provides an
opportunity for the programmer to perform time keeping
of several types. In the PICmicro, the clock also drives
hardware dedicated to timekeeping. The applications
may include keeping “real time”, or timing sensitive
processes
such as serial data communication. The accuracy
of these timing applications is dependent upon the
accuracy of the clock oscillator